/*
 ***********************************************************************
 ** md5.c -- the source code for MD5 routines                         **
 ** RSA Data Security, Inc. MD5 Message-Digest Algorithm              **
 ** Created: 2/17/90 RLR                                              **
 ** Revised: 1/91 SRD,AJ,BSK,JT Reference C Version                   **
 ** Revised (for MD5): RLR 4/27/91                                    **
 **   -- G modified to have y&~z instead of y&z                       **
 **   -- FF, GG, HH modified to add in last register done             **
 **   -- Access pattern: round 2 works mod 5, round 3 works mod 3     **
 **   -- distinct additive constant for each step                     **
 **   -- round 4 added, working mod 7                                 **
 ***********************************************************************
 */

/*
 ***********************************************************************
 ** Copyright (C) 1990, RSA Data Security, Inc. All rights reserved.  **
 **                                                                   **
 ** License to copy and use this software is granted provided that    **
 ** it is identified as the "RSA Data Security, Inc. MD5 Message-     **
 ** Digest Algorithm" in all material mentioning or referencing this  **
 ** software or this function.                                        **
 **                                                                   **
 ** License is also granted to make and use derivative works          **
 ** provided that such works are identified as "derived from the RSA  **
 ** Data Security, Inc. MD5 Message-Digest Algorithm" in all          **
 ** material mentioning or referencing the derived work.              **
 **                                                                   **
 ** RSA Data Security, Inc. makes no representations concerning       **
 ** either the merchantability of this software or the suitability    **
 ** of this software for any particular purpose.  It is provided "as  **
 ** is" without express or implied warranty of any kind.              **
 **                                                                   **
 ** These notices must be retained in any copies of any part of this  **
 ** documentation and/or software.                                    **
 ***********************************************************************
 */

#include "md5.h"

/*
 ***********************************************************************
 **  Message-digest routines:                                         **
 **  To form the message digest for a message M                       **
 **    (1) Initialize a context buffer mdContext using MD5Init        **
 **    (2) Call MD5Update on mdContext and M                          **
 **    (3) Call MD5Final on mdContext                                 **
 **  The message digest is now in mdContext->digest[0...15]           **
 ***********************************************************************
 */

/* forward declaration */
static void Transform(UINT4*, UINT4*);

#ifdef __STDC__
static const
#else
static
#endif
    unsigned char PADDING[64] = {0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};

/* F, G, H and I are basic MD5 functions */
#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))

/* ROTATE_LEFT rotates x left n bits */
#if defined(FAST_MD5) && defined(__GNUC__) && defined(mc68000)
/*
 * If we're on a 68000 based CPU and using a GNU C compiler with
 * inline assembly code, we can speed this up a bit.
 */
inline UINT4 ROTATE_LEFT(UINT4 x, int n)
{
    asm("roll %2,%0" : "=d"(x) : "0"(x), "Ir"(n));
    return x;
}
#else
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
#endif

/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4 */
/* Rotation is separate from addition to prevent recomputation */
#define FF(a, b, c, d, x, s, ac) \
    { \
        (a) += F((b), (c), (d)) + (x) + (UINT4)(ac); \
        (a) = ROTATE_LEFT((a), (s)); \
        (a) += (b); \
    }
#define GG(a, b, c, d, x, s, ac) \
    { \
        (a) += G((b), (c), (d)) + (x) + (UINT4)(ac); \
        (a) = ROTATE_LEFT((a), (s)); \
        (a) += (b); \
    }
#define HH(a, b, c, d, x, s, ac) \
    { \
        (a) += H((b), (c), (d)) + (x) + (UINT4)(ac); \
        (a) = ROTATE_LEFT((a), (s)); \
        (a) += (b); \
    }
#define II(a, b, c, d, x, s, ac) \
    { \
        (a) += I((b), (c), (d)) + (x) + (UINT4)(ac); \
        (a) = ROTATE_LEFT((a), (s)); \
        (a) += (b); \
    }

/* The routine MD5Init initializes the message-digest context
   mdContext. All fields are set to zero.
 */
void MD5Init(MD5_CTX* mdContext)
{
    mdContext->i[0] = mdContext->i[1] = (UINT4)0;

    /* Load magic initialization constants.
     */
    mdContext->buf[0] = (UINT4)0x67452301;
    mdContext->buf[1] = (UINT4)0xefcdab89;
    mdContext->buf[2] = (UINT4)0x98badcfe;
    mdContext->buf[3] = (UINT4)0x10325476;
}

/* The routine MD5Update updates the message-digest context to
   account for the presence of each of the characters inBuf[0..inLen-1]
   in the message whose digest is being computed.
 */
void MD5Update(MD5_CTX* mdContext, unsigned const char* inBuf, unsigned int inLen)
{
    UINT4 in[16];
    int mdi;
    unsigned int i, ii;

    /* compute number of bytes mod 64 */
    mdi = (int)((mdContext->i[0] >> 3) & 0x3F);

    /* update number of bits */
    if ((mdContext->i[0] + ((UINT4)inLen << 3)) < mdContext->i[0])
        mdContext->i[1]++;
    mdContext->i[0] += ((UINT4)inLen << 3);
    mdContext->i[1] += ((UINT4)inLen >> 29);

    while (inLen--) {
        /* add new character to buffer, increment mdi */
        mdContext->in[mdi++] = *inBuf++;

        /* transform if necessary */
        if (mdi == 0x40) {
            for (i = 0, ii = 0; i < 16; i++, ii += 4)
                in[i] = (((UINT4)mdContext->in[ii + 3]) << 24) | (((UINT4)mdContext->in[ii + 2]) << 16) | (((UINT4)mdContext->in[ii + 1]) << 8)
                        | ((UINT4)mdContext->in[ii]);
            Transform(mdContext->buf, in);
            mdi = 0;
        }
    }
}

/* The routine MD5Final terminates the message-digest computation and
   ends with the desired message digest in mdContext->digest[0...15].
 */

void MD5Final(MD5_CTX* mdContext)
{
    UINT4 in[16];
    int mdi;
    unsigned int i, ii;
    unsigned int padLen;

    /* save number of bits */
    in[14] = mdContext->i[0];
    in[15] = mdContext->i[1];

    /* compute number of bytes mod 64 */
    mdi = (int)((mdContext->i[0] >> 3) & 0x3F);

    /* pad out to 56 mod 64 */
    padLen = (mdi < 56) ? (56 - mdi) : (120 - mdi);
    MD5Update(mdContext, PADDING, padLen);

    /* append length in bits and transform */
    for (i = 0, ii = 0; i < 14; i++, ii += 4)
        in[i] = (((UINT4)mdContext->in[ii + 3]) << 24) | (((UINT4)mdContext->in[ii + 2]) << 16) | (((UINT4)mdContext->in[ii + 1]) << 8)
                | ((UINT4)mdContext->in[ii]);
    Transform(mdContext->buf, in);

    /* store buffer in digest */
    for (i = 0, ii = 0; i < 4; i++, ii += 4) {
        mdContext->digest[ii] = (unsigned char)(mdContext->buf[i] & 0xFF);
        mdContext->digest[ii + 1] = (unsigned char)((mdContext->buf[i] >> 8) & 0xFF);
        mdContext->digest[ii + 2] = (unsigned char)((mdContext->buf[i] >> 16) & 0xFF);
        mdContext->digest[ii + 3] = (unsigned char)((mdContext->buf[i] >> 24) & 0xFF);
    }
}

/* Basic MD5 step. Transforms buf based on in.
 */
static void Transform(buf, in) UINT4* buf;
UINT4* in;
{
    UINT4 a = buf[0], b = buf[1], c = buf[2], d = buf[3];

    /* Round 1 */
#define S11 7
#define S12 12
#define S13 17
#define S14 22

    FF(a, b, c, d, in[0], S11, 0xd76aa478);  /* 1 */
    FF(d, a, b, c, in[1], S12, 0xe8c7b756);  /* 2 */
    FF(c, d, a, b, in[2], S13, 0x242070db);  /* 3 */
    FF(b, c, d, a, in[3], S14, 0xc1bdceee);  /* 4 */
    FF(a, b, c, d, in[4], S11, 0xf57c0faf);  /* 5 */
    FF(d, a, b, c, in[5], S12, 0x4787c62a);  /* 6 */
    FF(c, d, a, b, in[6], S13, 0xa8304613);  /* 7 */
    FF(b, c, d, a, in[7], S14, 0xfd469501);  /* 8 */
    FF(a, b, c, d, in[8], S11, 0x698098d8);  /* 9 */
    FF(d, a, b, c, in[9], S12, 0x8b44f7af);  /* 10 */
    FF(c, d, a, b, in[10], S13, 0xffff5bb1); /* 11 */
    FF(b, c, d, a, in[11], S14, 0x895cd7be); /* 12 */
    FF(a, b, c, d, in[12], S11, 0x6b901122); /* 13 */
    FF(d, a, b, c, in[13], S12, 0xfd987193); /* 14 */
    FF(c, d, a, b, in[14], S13, 0xa679438e); /* 15 */
    FF(b, c, d, a, in[15], S14, 0x49b40821); /* 16 */

    /* Round 2 */
#define S21 5
#define S22 9
#define S23 14
#define S24 20
    GG(a, b, c, d, in[1], S21, 0xf61e2562);  /* 17 */
    GG(d, a, b, c, in[6], S22, 0xc040b340);  /* 18 */
    GG(c, d, a, b, in[11], S23, 0x265e5a51); /* 19 */
    GG(b, c, d, a, in[0], S24, 0xe9b6c7aa);  /* 20 */
    GG(a, b, c, d, in[5], S21, 0xd62f105d);  /* 21 */
    GG(d, a, b, c, in[10], S22, 0x2441453);  /* 22 */
    GG(c, d, a, b, in[15], S23, 0xd8a1e681); /* 23 */
    GG(b, c, d, a, in[4], S24, 0xe7d3fbc8);  /* 24 */
    GG(a, b, c, d, in[9], S21, 0x21e1cde6);  /* 25 */
    GG(d, a, b, c, in[14], S22, 0xc33707d6); /* 26 */
    GG(c, d, a, b, in[3], S23, 0xf4d50d87);  /* 27 */
    GG(b, c, d, a, in[8], S24, 0x455a14ed);  /* 28 */
    GG(a, b, c, d, in[13], S21, 0xa9e3e905); /* 29 */
    GG(d, a, b, c, in[2], S22, 0xfcefa3f8);  /* 30 */
    GG(c, d, a, b, in[7], S23, 0x676f02d9);  /* 31 */
    GG(b, c, d, a, in[12], S24, 0x8d2a4c8a); /* 32 */

    /* Round 3 */
#define S31 4
#define S32 11
#define S33 16
#define S34 23
    HH(a, b, c, d, in[5], S31, 0xfffa3942);  /* 33 */
    HH(d, a, b, c, in[8], S32, 0x8771f681);  /* 34 */
    HH(c, d, a, b, in[11], S33, 0x6d9d6122); /* 35 */
    HH(b, c, d, a, in[14], S34, 0xfde5380c); /* 36 */
    HH(a, b, c, d, in[1], S31, 0xa4beea44);  /* 37 */
    HH(d, a, b, c, in[4], S32, 0x4bdecfa9);  /* 38 */
    HH(c, d, a, b, in[7], S33, 0xf6bb4b60);  /* 39 */
    HH(b, c, d, a, in[10], S34, 0xbebfbc70); /* 40 */
    HH(a, b, c, d, in[13], S31, 0x289b7ec6); /* 41 */
    HH(d, a, b, c, in[0], S32, 0xeaa127fa);  /* 42 */
    HH(c, d, a, b, in[3], S33, 0xd4ef3085);  /* 43 */
    HH(b, c, d, a, in[6], S34, 0x4881d05);   /* 44 */
    HH(a, b, c, d, in[9], S31, 0xd9d4d039);  /* 45 */
    HH(d, a, b, c, in[12], S32, 0xe6db99e5); /* 46 */
    HH(c, d, a, b, in[15], S33, 0x1fa27cf8); /* 47 */
    HH(b, c, d, a, in[2], S34, 0xc4ac5665);  /* 48 */

    /* Round 4 */
#define S41 6
#define S42 10
#define S43 15
#define S44 21
    II(a, b, c, d, in[0], S41, 0xf4292244);  /* 49 */
    II(d, a, b, c, in[7], S42, 0x432aff97);  /* 50 */
    II(c, d, a, b, in[14], S43, 0xab9423a7); /* 51 */
    II(b, c, d, a, in[5], S44, 0xfc93a039);  /* 52 */
    II(a, b, c, d, in[12], S41, 0x655b59c3); /* 53 */
    II(d, a, b, c, in[3], S42, 0x8f0ccc92);  /* 54 */
    II(c, d, a, b, in[10], S43, 0xffeff47d); /* 55 */
    II(b, c, d, a, in[1], S44, 0x85845dd1);  /* 56 */
    II(a, b, c, d, in[8], S41, 0x6fa87e4f);  /* 57 */
    II(d, a, b, c, in[15], S42, 0xfe2ce6e0); /* 58 */
    II(c, d, a, b, in[6], S43, 0xa3014314);  /* 59 */
    II(b, c, d, a, in[13], S44, 0x4e0811a1); /* 60 */
    II(a, b, c, d, in[4], S41, 0xf7537e82);  /* 61 */
    II(d, a, b, c, in[11], S42, 0xbd3af235); /* 62 */
    II(c, d, a, b, in[2], S43, 0x2ad7d2bb);  /* 63 */
    II(b, c, d, a, in[9], S44, 0xeb86d391);  /* 64 */

    buf[0] += a;
    buf[1] += b;
    buf[2] += c;
    buf[3] += d;
}

/*
 ***********************************************************************
 ** End of md5.c                                                      **
 ******************************** (cut) ********************************
 */
